In the construction of concrete buildings and the like it is necessary, for a number of reasons, to pour the concrete in discrete sections. It is common practice to provide a waterstop in the joint between these sections. According to conventional practice, this waterstop consists of a ribbon of an elastomer material, one-half of which is embedded in the concrete of one section and the other half of which is embedded in the concrete of the immediately adjacent section. The waterstop in this way prevents the passage of water through the joint between the two concrete sections.
The waterstop network is laid in the forms before the concrete is poured and generally forms a continuous structure consisting of lengths of the waterstop band that are fastened together. Since the waterstop material only comes in lengths that can be easily handled and because the network is not continuously straight but must extend in various directions at the corners and joints in the building, it is necessary to cut the waterstop element and fasten it to a similar waterstop in various joint configurations. When the joint is an end-to-end connection, the customary procedure is to heat the ends of the waterstop (which is formed of a thermoplastic elastomer) and, while the ends are still in a molten material hardens and a continuous joint or weld is formed. While it is possible to make a butt joint in this manner, other types of junctions are not as easy to form, particularly where the waterstop extends in several directions from a given point. Furthermore, butt welding in this manner produces a very poor joint, because the operation must necessarily be performed in the field where conditions are not suitable for accurate heating and clamping. Furthermore, the use of a heating instrument to melt the thermoplastic means that dangerous fumes may be introduced into the air and breathed by the workmen who are assembling the waterstop. In other words, the old system of joining lengths of waterstop into a desired configuration is not only ineffective, but also dangerous. These and other difficulties experienced with the prior are devices have been obviated in a novel manner by the present invention.
It is, therefore, an outstanding object of the invention to provide a waterproof joint using a system for assembling waterstops that can effectively be used in the field.
Another object of this invention is the provision of a waterproof joint capable of field assembly under wet and dirty conditions.
A further object of the present invention is the provision of a waterproof joint for forming a junction in waterstops formed by a process which releases no dangerous fumes.
It is another object of the instant invention to provide a system for assembling waterstops in concrete construction in which the connections are strong and waterproof.
A still further object of the invention is the provision of waterproof joint that can be formed in the midst of concrete construction to provide effective waterproofing without danger to the workmen.
It is a still further object of the invention to provide a waterproof joint formed of elastomer materials which joint is simple in construction, which is inexpensive to use, and which is capable of a long life of useful service when buried in concrete and is, therefore, not available for maintenance.
It is still further object of the present invention to provide a waterproof joint system in which all necessary junctions of waterstops can be formed from a small number of standard elements without the necessity for cutting and shaping in the field.
With these and other objects in view, as will be apparent to those skilled in the art, the invention resides in the combination of parts set forth in the specification and covered by the claims appended hereto.